1. Field of the Invention
The present invention relates to a slider-pull-assembling unit for automatically assembling a pull onto a slider for opening/closing a slide fastener. More particularly, it relates to a slider-pull-assembling unit which enables effective transportation of sliders and assembly of a pull thereto in accordance with assembling steps.
2. Description of the Related Art
Conventionally, a unit for automatically assembling a pull onto a slider body by inserting an annular connecting portion of the pull into an opening formed in part of a pull-attachment lug of the slider body and then crimping the pull-attachment lug to close the opening has been already reduced to practice. Such a unit has been disclosed in, for example, Japanese Patent Publication No. 1-25563, Japanese Utility Model Publication No. 5-29603, Japanese Patent Publication No. 7-79726.
In the slider-pull-assembling units disclosed in the Japanese Patent Publication No. 1-25563 and Japanese Patent Publication No. 7-79726, a slider-body-transportation means and a pull-supply means are the same in principle. In these units, a slider body supplied from a slider-body-supply path is carried forward by a slider-body pusher. In front of the slider-body-supply path, a pull supplied from a pull-supply path waits in such a state that its annular connecting portion faces a position where an open end of a pull-attachment lug of the slider body passes. When the slider body is pushed and fed by the slider body pusher and the open end of the pull-attachment lug is inserted into the annular connecting portion of the pull, the pull-attachment lug is crimped by a lug-crimping apparatus so as to close the open end. Then, the pull is further pushed forward, thus the assembling of the pull is completed.
The aforementioned Japanese Patent Publication No. 1-25563 and Japanese Patent Publication No. 7-79726 are different from each other in that the lug-crimping apparatus of the former is comprised of a punch and a die which are driven under control while that of the latter is comprised of a punch roller which rotates in one direction and a supporting base.
On the other hand, in the slider-pull-assembling unit disclosed in the aforementioned Japanese Utility Model Publication No. 5-29603, equally spaced slider-accommodating portions are formed in an outer peripheral surface of a rotation disk that rotates intermittently. A pull is supplied obliquely from above to one of the slider-accommodating portions through a supply chute, and the supplied pull is held by a pull-holding member that advances/moves back horizontally with respect to a bottom end of the supply chute. At this time, the pull-holding member keeps an annular connecting portion of the pull facing the slider-accommodating portion. In this state, the pull-holding member moves back so as to insert the annular connecting portion onto an open end of a pull-attachment lug of the slider body. After that, a rear holding piece of the pull-holding member is moved back while a front holding piece thereof is lowered so as to crimp the pull-attachment lug, thereby closing the open end of the pull-attachment lug.
However, according to the pull-assembling unit disclosed in the aforementioned Japanese Patent Publication No. 1-25563, the slider-body pusher, which pushes and carries a slider body from the slider-supply chute to a crimping position of the pull-attachment lug's open end via the pull-supply chute, keeps its extended state until the pull-attachment lug's open end is crimped and closed at the open end crimping position, and after the crimping is completed, the slider body pusher starts moving back. Therefore, advancement and moving back are performed for a single assembling. As a result, it takes a long time to complete an assembly of the pull onto the slider body, so that the assembly cannot be carried out at a high speed. Further, in the slider-pull-assembling unit disclosed in the aforementioned Japanese Patent Publication No. 7-79726, because the slider-body pusher advances and moves back for every assembly of the pull onto the slider body, it has the same problem as described above.
Further, there is a problem common to the pull-assembling units of these patent publications. While the open end of the pull-attachment lug of the slider body is inserted into the annular connecting portion of the pull, and then the slider body is pushed and carried to a crimping position of the crimping unit at a subsequent process, the open end of the pull-attachment lug is kept open. Moreover, the slider body is forcibly pushed forward and carried with the pull held by the supply chute in an elastic state being hooked on the open end of the pull-attachment lug of the slider body. Thus, when the pull is extracted from the pull-supply chute resisting the elasticity, a free end of the pull tends to jump up so that the pull is easy to slip out of the open end of the pull-attachment lug. This slip-out is more likely to occur as the unit processing speed is accelerated.
In the pull-assembling unit disclosed in the aforementioned Japanese Utility Model Publication No. 5-29603, not only a structure of the holding member is complicated, but also it is difficult to keep an accurate timing between the rotation disk and the holding member and an accurate timing of complicated actuation of the holding member itself for a long time. Further, it takes considerably a long time for maintenance and control of these components.